Natural vs. Fake Black Diamonds | How Valuable are they?

Natural vs. Fake Black Diamonds | How Valuable are they?

Natural vs. Fake Black Diamonds | How Valuable are they?

Black diamonds have grown in popularity over the years due to their captivating and mysterious appeal. Unfortunately, with that growth comes an increased risk of fake or treated stones flooding the market. This article will look at ways to identify genuine black diamonds and distinguish them from fake or treated stones. Prices for such gemstones typically range between $1,500-$3,000 per carat for weights ranging from 1.00 carats up to 3.00 carats.

On the other hand, colorless diamonds may range in value from $2,500 to $153,000 per carat for clear diamonds weighing 1.00 – 3.00 carats.

What is a black diamond?

A black diamond, also known as carbonado, is an organic gemstone with an intense black hue due to numerous graphite inclusions that absorb light and give the stone its opaque black appearance. Unlike other colored diamonds, black diamonds aren’t graded based on the color scale but on clarity and size.

How to Spot a Real Black Diamond

Discover how to identify an authentic black diamond by inspecting its face.

Look for Inclusions: Black diamonds possess an intriguing structure with visible inclusions or graphite particles, giving the stone its black hue. These inclusions should be visible to the naked eye and appear as small black specks or dots within the rock.

Test its hardness: Black diamonds, like all diamonds, are incredibly hard and have a Mohs scale rating of 10. So if you scratch something with the black diamond and it leaves behind a mark, it’s likely not an authentic diamond.

Verify the weight: Black diamonds tend to be denser than other colored diamonds and weigh more. Therefore, if a stone appears lighter than expected for its size, it could not be an authentic black diamond.

Utilize a Thermal Conductivity Tester: Diamonds boast high thermal conductivity, meaning they dissipate heat rapidly. Using a thermal conductivity tester, you can determine whether your stone is made of diamonds or another material.

Ensure that It’s Certified: To guarantee that you purchase a genuine black diamond, have it certified by an established gemological laboratory such as the Gemological Institute of America (GIA) or International Gem Institute (IGI). These laboratories will provide documentation of the stone’s quality and authenticity.

How to Spot a Fake Black Diamond

Do you want to learn how to identify a fake black diamond? Here’s how:

Look for Uniformity: Fake black diamonds are often created in laboratories with even color and appearance, whereas real black diamonds possess natural patterns of inclusions that give them a unique appearance.

Check for light reflection: A natural black diamond will have a dull, matte appearance due to its opaque nature; however, fake black diamonds may exhibit a shiny or reflective surface.

Testing Weight: Black diamonds tend to be denser than other colored diamonds and thus heavier. If a diamond feels lighter than expected for its size, it could be an imitation black diamond.

Utilize a Thermal Conductivity Tester: You can also use this tool to determine if a black diamond is fake. For example, suppose the stone does not disperse heat rapidly. In that case, it could be indicative of being an artificial black diamond.

Verify its Authenticity: If you think a black diamond may be fake, have it certified by an established gemological laboratory. They will provide documentation of the stone’s authenticity and quality.

How to recognize a treated black diamond

Look for color zoning: Treated black diamonds may exhibit color zoning, which refers to an uneven distribution of hues throughout the stone. That is typically due to irradiating the diamond with lasers to enhance its hue.

Check for surface imperfections: Treated black diamonds may have visible surface flaws due to the treatment process, which can help identify them as having been treated.

Thermal Conductivity Tester: Treated black diamonds may have lower thermal conductivity than natural black diamonds, so using a thermal conductivity tester can help distinguish between them.

Certification Is Essential: If You Suspect Something, have it certified! Before considering whether a black diamond has been treated, it must be certified by an established gemological laboratory. They can determine if the stone has been altered and provide documentation of its quality and authenticity.

Grades and Value of Black Diamond

Black diamonds are graded using the same criteria as colorless diamonds, including the 4 Cs: color, clarity, cut, and carat weight. However, black diamonds have their unique grading system, as their color and clarity are evaluated differently than colorless diamonds.

The different grades of black diamonds are:

  1. Natural Fancy Black: This is the highest grade of black diamond and is completely natural, meaning it has not been treated or enhanced. These diamonds are deep, rich black in color, and have a uniform color distribution throughout the stone. They may have slight inclusions or blemishes, but these do not detract from the stone’s beauty. Natural fancy black diamonds are rare and valuable.
  2. Treated Black: Treated black diamonds have been treated to enhance their color or clarity. These diamonds may be less valuable than natural fancy black diamonds, as the treatment process can affect the stone’s durability and long-term value. However, well-treated black diamonds can still be quite beautiful and valuable.
  3. Natural Black with Visible Inclusions: These diamonds are natural but have visible inclusions or blemishes that can detract from their value. However, some people appreciate the unique beauty of these diamonds and may be willing to pay a premium for them.
  4. Heat-Treated Black: Heat-treated black diamonds are diamonds exposed to high temperatures to enhance their color. While heat treatment can improve the stone’s color, it can also make the diamond more brittle and prone to cracking. Heat-treated black diamonds are generally less valuable than natural fancy black diamonds.

The value of a black diamond is determined by its grade, as well as its size and origin. Natural fancy black diamonds are the most valuable, followed by well-treated black diamonds. Natural black diamonds with visible inclusions and heat-treated black diamonds are less valuable.

Where to Purchase Black Diamonds

When looking for a black diamond, you must purchase it from an established dealer. Look for those members of the Gemological Institute of America (GIA) or other recognized industry groups, plus those with positive reviews and ratings from previous customers.

Online marketplaces such as Blue Nile and James Allen provide a vast selection of black diamonds with detailed information on each stone’s quality and certification. However, it is essential to exercise caution when purchasing diamonds online; only purchase from reliable sellers.

Where to Sell Black Diamonds

If you’re looking to sell your black diamond, several options exist. First, you could sell it locally to a jeweler, pawnshop, or diamond buyer; however, an established appraiser should appraise the stone before doing so to guarantee you receive fair value.

You can sell black diamonds online through trusted marketplaces such as Worthy or Diamond Buyers International. These sites will provide a free appraisal and competitive prices for your stone.

In conclusion, accurately identifying and distinguishing a black diamond from fake or treated stones necessitates close observation and testing. Look for visible inclusions, assess their hardness and weight with a thermal conductivity tester, then consider having them certified by an established gemological laboratory. Finally, when buying or selling black diamonds, work with trustworthy dealers who will appraise your stone by an expert to guarantee a fair price.

How Valuable Are Black Diamonds?

Black diamonds are renowned for their mysterious and captivating beauty, but their value can fluctuate drastically based on several factors. On average, black diamonds tend to be less valuable than colorless diamonds; however, they could still be highly valued gems depending on their size, quality, and origin.

Black diamonds can be quite valuable. Here are some of the most expensive black diamonds in the world:

  1. The Black Orlov: Also known as the Eye of Brahma diamond, this 67.5-carat black diamond is named after its previous owner, Russian princess Nadia Vyegin-Orlov. The diamond is believed to have been mined in India and was reportedly cursed due to its association with the Hindu god Brahma. Despite its dark history, the Black Orlov is a stunning and valuable diamond, estimated to be between $300 million and $400 million.
  2. The Amsterdam Diamond: This 33.74-carat black diamond was discovered in South Africa in 1972 and was cut and polished in Amsterdam. The diamond is unusual because it has a pear-shaped cut and a flat bottom, a rare and desirable feature in black diamonds. The Amsterdam Diamond is estimated to be worth over $25 million.
  3. The Gruosi Diamond: This 115.34-carat black diamond was named after its owner, Swiss jeweler Fawaz Gruosi. The diamond is unusual in its rough, uncut surface, giving it a natural and organic appearance. The Gruosi Diamond is estimated to be worth over $20 million.
  4. The Spirit of de Grisogono: This 312.24-carat black diamond is the largest cut black diamond in the world and was once owned by the Swiss luxury jeweler de Grisogono. The diamond was discovered in West Central Africa. It was cut into a rectangular shape with 702 smaller white diamonds surrounding it. The Spirit of de Grisogono is estimated to be worth over $20 million.
  5. The Korloff Noir: This 88-carat black diamond was named after its previous owner, Russian nobleman Korloff-Sapojnikoff. The diamond is unusual because it has a cushion cut with 57 facets, giving it a brilliant and fiery appearance. The Korloff Noir is estimated to be worth over $20 million.

Factors affecting the value of black diamond


Like all diamonds, the size of a black diamond significantly impacts its value. Black diamonds tend to come in smaller sizes, and larger stones are rare, making larger stones highly sought-after items of high quality.


Several factors determine a black diamond’s quality, including color, clarity, cut, and carat weight. Color plays a particularly significant role in black diamonds as their darkness and hue uniformity can significantly impact their value. Ideally, your black diamond should exhibit deep hues with no visible color zoning or inclusions.


Clarity is also essential for black diamonds, though less so than colorless stones. Slight inclusions or blemishes can add to a black diamond’s unique beauty, giving it an organic and natural appearance. On the contrary, large inclusions or blemishes may detract from its value.


Cut is another critical factor when assessing the value of a black diamond. Like colorless diamonds, black diamonds are generally cut in round or cushion shapes to maximize their brilliance and fire. However, some black diamonds may be cut into more unusual shapes or used in unique jewelry designs, which could affect their value significantly.


The location of a black diamond can influence its value. Black diamonds are commonly mined in Brazil, Central Africa, and India but can also be found elsewhere worldwide. Diamonds mined from specific places may be more valuable due to their rarity and unique characteristics.